Dressing mechanism for grinding wheels



July 4, 1944. J. SNADER DRESSING MECHANISM FOR GRINDING WHEELS Original Filed Aug. 3, 1940 Patented July 4, 1944 DRESSING MECHANISM FOR GRINDING WHEELS Ira J. Snader, Detroit, Micln, assignor to Ex- Cell- Corporation, Detroit, Mich., a corporation of Michigan Original applications December 2, 1937, Serial No. 177,693, and August 3, 1940, Serial No. 350,362. Divided and this application July 28, 1941, Se-

rial No. 404,289

4 Claims.

The present invention relates to improvements in dressing mechanisms for grinding wheels, and has particular reference to such mechanisms adapted for use in machine tools.

One of the objects of the invention is to proting contours.

adjustment.

parent as the description proceeds. In the accompanying drawing,

features of my invention.

line 2-2 of Fig. 1.

line 3--3 of Fig. 1.

spirit and scope of the invention as expressed in the appended claims.

internal threads.

177,693, filed December 2, 1937, 2,251,961, dated August 12, 1941).

grinding wheel 8.

5 grinding wheel is disclosed and claimed in 3m! vide a novel dressing mechanism which is quickly, copending application, Serial No. $0,362, 'filed" conveniently and accurately adjustable to provide August 3, 1940, of which the present application the grinding wheel selectively with different cutis a division.

The dressing mechanism herein shown com- Another object resides in the provision of a prises a base slide l2 mounted on ways l9 for new and improved dressing mechanism which is adjustment longitudinally of the headstock 9, adjustable relative to th grinding wheel and and adapted to be secured in position of adjustwhich may be quickly actuated into and out of ment by a clamp screw II. The base slide I2 is dressing position without disturbing the dressing formed on the top with transverse ways l5 supporting an adjusting slide it for movement to- Other objects and advantages will become 841- Ward and from the grinding wheel 8. An adjusting screw l1, provided with a graduated hand knob I8, is rotatably anchored in a depending Figure 1 is a plan view, partially in horizontal lug 19 on the front end of the slide l6, and is in section, of a dressing mechanism embodying the 20 threaded engagement with a fixed nut 20 on the slide I2.

Fig. 2 is a vertical sectional view taken along Mounted on ways 2| on the slide 16 for quick adjustment into and out of dressing position is Fig. 3 is a vertical sectional view taken along a retracting slide 22 supporting a hand dresser 23. The slide 22 is formed with an elongated While the invention is susceptible of various longitudinal slot 24.

modifications and alternative constructions, I hand lever 29, extends through the slot 24 and have shown in the drawing and will herein deinto threaded engagement with the slide l6, and scribe in detail the preferred embodiment, but is adapted to lock the slide 22 in position of adit is to be understood that I do not thereby in justment. A pin 2'! extends through the slide tend to limit the invention to the specific form 22 into the outer end of the slot24, and is adaptdisclosed, but intend to cover all modifications ed for engagement with the bolt 25 to locate the and alternative constructions falling within the dresser 23 in operative position. Accurate dressing adjustment is obtained by means of the fine screw l'l, while the pin 21 is against the stud The dressing mechanism constituting the ex- 25. Thereafter, the dresser 23 may be retracted emplary embodiment of the present invention, to clear the bracket 5 by simply loosening the although not limited in its broad aspects to any bolt 25 and moving the slide 22 forwardly as particular type of grinding machine, is espepermitted by the S ot and may be quickly cially suited for a machine adapted to grind 40 returned into operative position, as determined Such a machine is disclosed by agement of the pin 21 with the bolt, within detail in my copending application Serial No, out requiring adjustment of the screw 11.

(Patent No. The dresser 23 comprises a swivel plate 28 which The machine is mounted in a bore 29 opening through the is adapted also for grinding external screw rear end of the slide 22 for rotary adjustment threads and is converted for internal grinding by about a vertical axis. the substitution of a suitable spindle structure. extend across the plane of the wheel adjacent In the present instance this structure comprises t0 the periphery thereof and the plate axis ina split bracket 5 removably mounted on the front tersects the plane of the wheel and is substanof a tool fixture 6, and supporting a tool spindle tially perpendicular to the wheel axis. The plate '6. One end of the spindle 1 projects laterally 28 has a graduated flange 39 overlying the slide from the bracket 6, and supports an internal 22, and a hand lever '3! for facilitating adjust- The dressing mechanism for ment. the internal grinding wheel 8 is adapted to be plate 28 and has a locking flange 33 underlymounted on a headstock 9 on a work table II! reciprocable on the machine base II, and nor-- mally adapted to support a work blank (not shown) for rotation and for longitudinal reciprocation. A dressing mechanism tor an external A clamp bolt 25, with a The plate is located to A stud 32 extends through the swivel ing the slide 22. A knurled knob 34 is threaded onto the upper end of the stud 32, and when tightened serves to secure the plate 28 in position of adjustment.

The plate 28 is formed with a depending eccentric bracket li. Mounted in antifriction bearings 06 in the lower end of the bracket 35 is a pivot shaft 31 supporting a generally vertical lever II. This lever projects upwardly through a slot II in the plate 28, and at the lower end supports an adjustable dressing tool 40 in opposition to the periphery of the wheel. The path described by the tool lies about on an axial plane of the wheel.

The swivel plate 28. is adjustable through 180 degrees to permit location of the tool 40 in different selective dressingipositions. Suitable accurately adjustable stops 4| are provided for loeating the tool 40 quickly in position for dressing the oppositely inclined faces of the grinding wheel 8. Thes stops comprise two line thread parallel screws (see Fig. 1) which are threaded in the slide 22 to extend into opposite sides of the bore 2-8, and project tangentially into an annular groove 42 in the swivel plate 28 for engagement respectively with limit pins 43. Each of the pins 43 is threaded vertically through the groove 42 into a tapered seat which eliminates any error due to clearance. To dress the root cutting face of the wheel 8. the swivel platen is adjusted into a position intermediate the flank cutting positions with the aid of the graduated flange Ill.

The dressing attachment is approximately 7 aligned with the grinding wheel 8 by movement of the table ill into position. The final precise adjustment is made with an indicator M.- This indicator is mounted on the base section Ii, and is adapted for engagement by a contact screw 45 adjustably mounted in a bracket 46 on the table ill. Then the dresser is actuated to true the wheel 8.

I claim as my invention:

1. A dressing mechanism comprising, in combination, a support, a member slida-ble on said support, a feed slide molmted on said member for movement transversely of said member, means for adjusting said slide. a quick-adjustment slide mounted on said feed slide for movement transversely of said member and formed with a longitudinal slot, a clamp bolt extending through said slot into threaded engagement with said feed slide, a stop pin adjustably threaded into one end oi said slot and adapted to coact with said bolt to locate said quick-adjustment slide in operative position, and a dressing device mounted on said quick-adjustment slide.

2. A dressing mechanism for grinding wheels comprising, in combination, a support formed with a bore, a circular plate rotatably mounted in said bore and formed with a peripheral groove, two limit stop pins Bdjustably threaded through said support tangentially into opposite aideg of said groove, two pins adapted to be inserted in different selective positions in said plate to project into said groove for engagement respectively with said stop pins to define opposite limit positions of said plate, means for securing said plate in a selected position of adjustment, a bracket on said plate, and a dressing tool holder operativeiy mounted on said bracket.

3. In a dressing mechanism of the character described, the combination of a pair of superimposed slides movable toward and away from g a grinding wheel on a line generally perpendicular to the axis thereof, means for accurately determining the position of said slides as a unit, one of said slides being freely movable relative to the other between advanced and retracted positions. an. adjustable abutment carried by one slide and engageable with the other slide for determining the advanced position of the freely movable slide, clamping means for securing the freely movable slide against such movement, a dressing tool pivotally mounted on the rapidly movable slide, and means for actuating said tool through a dressing stroke.

4. In a dressing mechanism of the character described, the combination of a pair of superimposed slides movable toward and away from a grinding wheel on a line paralleling the plane thereof, means for accurately determining the position of said slides as a unit, means providing for limited free sliding movementof one of said slides relative to the other and with respect to such accurately determined position, releasable means for securing the slides together, a member mounted at the end of the freely movable slide adjacent the grinding wheel for circular adjustment substantially in the plane of'said slide, an eccentric arm extending from said member to a radially outward position relative to the periphery of the grinding wheel, and a dressing tool pivotally mounted on said arm for swinging movement across the surface to be dressed as deter- IRA J. SNADER. 

